Hello, SFIA audio listeners. In this month's Nebula exclusive, big alien theory,

we're asked at the reason alien civilizations might be rare is because most aliens are huge.

To hear it and every episode early and ad-free, plus hours of bonus content,

check out go.nebola.tv slash Isaac Arthur and use my code, Isaac Arthur.

In the grandeur of the universe, the tapestry of life may be woven from strange or threads

than we ever dared to dream, and spun from materials far different to our own.

As we've studied the immensity of the cosmos, we've spent decades searching for life as we know it, clinging to the belief that the universe must be teeminging with carbon-based

organisms like ourselves.

But what if life's building blocks are not limited to the familiar

carbon atoms that compose our DNA and proteins? What if, out there are among the stars,

there exist beings unlike anything we've ever imagined, life forms fashioned from the silicon

of alien worlds. Today, we'll embark on a journey of imagination and scientific exploration to ponder the

possibilities of silicon-based life forms, creatures that could thrive in environments hostile

to all kind and challenge our very understanding of life itself.

I am your host, Isaac Arthur, and I hope you'll join me today as we delve into the realms of

silicon-based biology, where the chemistry of the cosmos takes on new and exotic forms.

This is not our first look at alternative chemistries for life, and when we explored

ammonia-based life forms earlier this year, there were many requests that we should look

at other chemistries,

silicon-based life forms being foremost amongst them.

We may cover those others down the road, but Silicon turns out to be a big enough topic on its own, so grab a drink and a snack, and relax.

We'll be here for a bit, and make sure you like and subscribe to the show, and hit the notifications

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